1,720,954 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Quantum carbon points on paper for the determination of copper ions in cachaça using a fluorimeter based on LED-UV and smartphone
No full textNo presente trabalho foi desenvolvido um procedimento simples e de baixo custo para a síntese de nanopartículas de carbono fluorescentes (CDs) a partir do amido presente no arroz por um processo hidrotérmico. Pela primeira vez na literatura é reportado um trabalho empregando nanopartículas de carbono para determinação de cobre em cachaça por meio da utilização de um dispositivo a base de papel (PAD) acoplados a uma placa 3D, tendo como fonte de excitação dos CDs uma câmara (LED-UV) com aquisição e análise de imagens digitais realizada por um smartphone. Os CDs sintetizados foram caracterizados por meio das técnicas de espalhamento dinâmico de luz, espectroscopia de fluorescência, espectrofotometria de absorção molecular na região do ultravioleta e visível, microscopia eletrônica de varredura, além disso foram realizados estudos do potencial zeta, pH e força iônica. O método proposto é baseado na atenuação da fluorescência emitida pelo complexo CDs/CPZ induzida pela presença de íons Cu2+. Para excitação do complexo CDs/CPZ foi construída uma câmara contendo quatro diodos LED-UV com máximo de emissão a 370 nm com uma abertura na parte superior permitindo o acoplamento do smartphone. As nanopartículas sintetizadas se mostraram seletivas para a determinação de cobre, por meio da funcionalização com bis(ciclohexanona) oxaldihidrazona (CPZ). Obteve-se uma resposta linear entre a concentração de cobre em solução em relação ao canal R e o B do modelo matemático de cores RGB em uma faixa linear de 2 a 13,2 mg L-1 com um R2 = 0,9944, e 25 a 7,2 mg L-1 com um R2 = 0,9993. Não houve a necessidade de adição de padrão ou padrão interno uma vez que os resultados de veracidade do método indicaram que a porcentagem de recuperação variou entre 85% e 111%, demonstrando que não há efeito de matriz. Foram obtidos LD e LQ, respectivamente, de 0,66 e 1,55 mg L-1 para o canal R e 0,23 e 0,62 mg L-1 para o canal B. Amostras de cachaças foram analisadas pelos métodos propostos e pelo método de referência, a partir dos resultados obtidos foi empregando o teste t pareado com 95% de confiança, o qual indicou não haver diferenças significativas nos resultados obtidos. Palavras-chave: Cobre. Fluorescência. PAD. Cachaça. Análise de Imagens Digitais. Carbon Dots. Nanopartículas. Impressão em 3D. Fluorímetro. LED.In the present work, a simple and low cost procedure was developed for the synthesis of fluorescent carbon nanoparticles (CDs) from the starch present in rice by a hydrothermal process. For the first time in the literature, a work is reported using carbon nanoparticles for the determination of copper in cachaça using a paper-based device (PAD) coupled to a 3D plate, with a camera (LED-UV) as the excitation source for the CDs with acquisition and analysis of digital images performed by a smartphone. The synthesized CDs were characterized by the techniques of dynamic light scattering, fluorescence spectroscopy, molecular absorption spectrophotometry in the ultraviolet and visible region, scanning electron microscopy, in addition to studies of zeta potential, pH and ionic strength. The proposed method is based on the attenuation of fluorescence emitted by the CD / CPZ complex induced by the presence of Cu2+ ions. For excitation of the CDs / CPZ complex, a chamber was built containing four UV-LED diodes with maximum emission at 370 nm with an opening at the top allowing the smartphone to be coupled. The synthesized nanoparticles proved to be selective for the determination of copper, by means of functionalization with bis (cyclohexanone) oxaldihidrazone (CPZ). A linear response was obtained between the copper concentration in solution in relation to the R channel and the B of the mathematical model of RGB colors in a linear range of 2 to 13.2 mg L-1 with an R2 = 0.9944, and 25 to 7.2 mg L-1 with an R2 = 0.9993. There was no need to add a standard or internal standard since the results of the method's veracity indicated that the percentage of recovery varied between 85% and 111%, demonstrating that there is no matrix effect. LD and LQ were obtained, respectively, of 0.66 and 1.55 mg L-1 for channel R and 0.23 and 0.62 mg L-1 for channel B. Samples of cachaça were analyzed by the proposed methods and by the reference method, based on the results obtained, the t-test paired with 95% confidence was used, which indicated that there were no significant differences in the results obtained. Keywords: Copper. Fluorescence. PAD. Cachaça. Digital Image Analysis. Carbon Dots. Nanoparticles. 3D printing. Fluorimeter. LED.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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